<!DOCTYPE html>
<html lang="en">

<head>
  <meta charset="UTF-8">
  <meta http-equiv="X-UA-Compatible" content="IE=edge">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>Document</title>
  <script src="../react18/react.development.js"></script>
  <script src="../react18/react-dom.development.js"></script>
  <script src="../react18/babel.min.js"></script>
</head>

<body>
  <div id="app"></div>
  <script type="text/babel">

    /* class App extends React.Component{
    
      state = {
        count:0
      }

      render(){
        const {count} = this.state;
        return (
          <div>
            <button onClick={this.handle} >+</button>
            <p>{count}</p>
          </div>
        )
      }

      //事件函数
      handle = () => {
        //当前this再箭头函数中，所以出去找this指向了，找到了App类，因为类其实就是构造函数，构造函数的this指向实例化对象，所以这个this指向实例化对象
        console.log(this);
      }
    }

    const root = ReactDOM.createRoot(document.getElementById('app'));
    root.render(<App/>) */


    class App extends React.Component{
      state = {
        count: 666
      }

      render(){
        const {count} = this.state;
        return (
          <div>
            <button onClick = {this.handel}>+</button>
            <p>{count}</p>
          </div>
        )
      }

      //事件函数
      handel = () =>{
        alert(1)
        //当前this再箭头函数中，所以出去找this指向了，找到了App类，因为类其实就是构造函数，构造函数的this指向实例化对象，所以这个this指向实例化对象
        console.log(this);
      }

    }


    const root = ReactDOM.createRoot(document.getElementById('app'));
    root.render(<App/>)
  


  </script>
</body>

</html>